[BB_cuda]

I been to my favorite bone yard lately collecting stuff for an M3 suspension conversion where i can. Side story for the top of the thread though. I had scored a partial M3 strut brace setup but lacked a couple parts and ultimately gave in and bought the missing pieces new.

Anyway, so I tear down the cowl and remove the black steel strut brace. I remove the central firewall panel. When i got the parts from the yard, We had to play a game to get the central V piece (i call it the boomerang) by rmoving the rubber snorkels from the central panel on a wrecked E92 M3. I ended up getting those rubber snorkels but not really thinking they were needed. I left the panel laying on the front clip at the yard. Wrong move there .... maybe.

Back to today's work. I look at my panel from 2011 335D and the snorkels are molded into it. Not removable. The snorkels have to come off the panel to get the boomerang in. So, I'm researching to see if i just use exacto and gut mine a=out and pop in these removable M3 ones or if i have to go back to bone yard and get that M3 one. That salvage yard guy is going to rake me over cost wise for the one little part. I always work out better value wise when i make a big haul. This is same place i scored the ECU and rear diff from.

For those interested, they do out of town deliveries. Amir is a great guy. Lonestar Imports in Houston. Here is a picture explaining it better. I need to go over to suspension section as surely someone else has tripped over same problem.

[BB_cuda]

and here is the 2011 dilemma I see.
http://www.e90post.com/forums/showth...M3+strut+brace

[BB_cuda]

I got sharp knife from kitchen and cut out the molded on snorkels. I test fit the removable ones and they wouldn't go up far enough. I learned that the "lips" of the molded ones needed to be cut out down to sort of a groove in the hard plastic cover. The removable boots then went in deep enough. The only problem left was the white plastic teeth on the back side didn't have anywhere to lock onto. I dremeled a little slot for the two teeth on each back side. It wasn't perfect but it worked. I used a dremel bit that was almost like a little needle.

The boots don't stay perfectly locked in but this is a doable solution. If i go to the yard again, i will look for a panel that is earlier than 2011. post #2 above implies that 2011 has a change in the this part to mold on the boots but i hadn't confirmed that yet. I tried to hunt in real oem for the part number molded into the panel but never could find anything.

Attached are pictures in a sequence. To install into the car, you can not put the panel with boomerang and snorkels all installed. You have to piece meal install the boomerang, then panel, then snorkels. I found that the last thing to be installed after several others was the large central bolt of the boomerang. I found that to get enough clearance for the boomerang, i had to remove the back part of engine cover. After boomerang, replace the back cover, then panel goes on over each leg of boomerang but have to slide over to other side to put other leg into panel hole. Replace the 10 mm hex screws of panel. Next you can slide on the boots.

One side of my boomerang had a stud that i never could remove even with 2 nuts locked together very tightly. Pushing boot over this side (right one) was a little more tricky.I found it was easier to slide boots if they were lubricated with a little armor all. Then i tried my best to lock the teeth of the white clips but was completely blind as to if they were really locking.

Once the boots were on and locked in, the rest of the job was more straight forward. Recall that i have the M3 cowl so the nuts and studs sticking up aren't a problem for me. The standard cowl does have some interference i have read. I went easy on the three nuts that hold the black rings to the strut towers. I've seen a couple examples on threads where people broke the studs off by over torquing. I had three old collar nuts from bone yard and purchased three new ones. I put blue loctite on the old ones. I reused as the damn collar nuts are $10 each new.

My final cost was pretty good considering a full up new M3 strut brace kit costs $425 these days at Tischer. I got a partial set up for $50 at salvage yard. This was boomerang, 2 black strut tower rings, ONE of the straight aluminum pieces, 3 collar nuts, 2 snorkels with plastic teeth rings, and central bolt for boomerang. I had to buy the 2 tower ring caps, one straight aluminum piece, and 3 more collar nuts for $130 +tax. I bought several stainless 8 mm nuts, washers, (1) 8 mm stud, and (2) 8 mm screws for $13 from Ace h/w. So, I built this thing for $193.

[WreckerX5d]

Thanks for the writeup. Now I know what to look for when I install my M3 strut brace. I didn't want to get it, but the coilovers I ordered interfere with the original one, like so (not my car):

[BB_cuda]

Here is where i learned lots of things for this mod. Credit Calwaterboy from "the fest" for showing me this in his M3 suspension mod writeup.

http://www.billswebspace.com/335M3St...stallation.htm

I knew to not attempt the link's method of putting panel/boomerang/boots based on Calwaterboy's struggle with this method. It is even harder for us due to the back portion engine cover's presence. It was a chicken and egg thing for me with regard to cover. In other threads where we talked method of intake pull, it was stated that back cover is more easily removed with central panel out. Well, I also found it sort of hard to get boomerang into the right spot with back cover on. Sooooo, I had to have the fun of putting back cover on AFTER the boomerang was successfully positioned. Then, another "fun" thing was sliding the panel over the boomerang's legs into the panel's holes with back cover back on. Needless to say, i was a little upset when i put boomerang/panel/boots back and had forgotten to put engine back cover back on. So, off came everything again except the boomerang.

Intake pull for cleaning and glow plugs/controller maintenance just got more "fun". There is a member named feuer that used his black steel bars and cut them on the outboard ends, smashed them down, and drilled them to bolt onto the black rings. Me thinks this might be a way to avoid all of this complexity. I don't know if it is as rigid (maybe more rigid) as the aluminum boomerang connection to firewall.

Feuer did this to save money and only buy the outer black rings, studs, nuts, collar nuts (too dang high $$), and black caps.

Here is his thread showing that method:
http://www.e90post.com/forums/showthread.php?t=1128637

[BB_cuda]

Pictures of the completed project. I was tired last night and the lighting wasn't good. So, i waited until today to get better shots.

[feuer]

Originally Posted by Wrecker335d

Thanks for the writeup. Now I know what to look for when I install my M3 strut brace. I didn't want to get it, but the coilovers I ordered interfere with the original one, like so (not my car):

Very stupid, who ever that person is!

[BB_cuda]

I found an ancient thread that HP Autosport started concerning this panel.
http://www.1addicts.com/forums/showt...=429896&page=2

See his post #1 and then skip to posts #35 through #40. The part number for the panel is 64-31-6-979-758 for the M3 panel that the boots can be installed into.

The two snorkel boots are:
Left: 64-31-6-964-415
right: 64-31-6-964-416

Post #43 shows that a guy was able to put the boomerang into a 2011 type panel and install WITHOUT CUTTING off the integral boots. Pick your poison. The above panel picture ( I googled that panel p/n) does have a lip where the boots would lock in better than my cut one did though.

I know that its pretty hard to get the panel out of the M3 car with boomerang still within it. We pulled pretty hard upward on the windshield wiper cowl to try to get clearance but no cigar. We couldn't get it to come out.

one of those boots got partially torn so I may try to find another.

[335dlci]

Cuda, it looks like your braces are upside down.

[BB_cuda]

Originally Posted by 335dlci

Cuda, it looks like your braces are upside down.

Maybe my brace is driving in Australia,

I wanted the BMW label to show on the aluminum bars. The part is same with either side up. The ends are definately different though. One end has set of normal holes and the other end has set of elongated holes.

[335dlci]

I just saw the sides are rounded off do they fit in the groove per say where it bolts to the strut mount side

[BB_cuda]

I took the straight pieces off today. I found the right panel and boots at salvage yard today. Cleaned them up real nice and switched out the panel. Donor was a 2008 328i.

335dlci. I looked closely at the ends and saw the concave surface and realized they should face down to grip the black end rings' connection point. I agree with you. The labels on the bars should point down. I got the salvage panel complete with good boots for $15. The yard guy and I had to hunt through 3 different cars before we found a good one. First one was melted and second one broken in half. Both had good removable boots though.

[335dlci]

Originally Posted by BB_cuda

I took the straight pieces off today. I found the right panel and boots at salvage yard today. Cleaned them up real nice and switched out the panel. Donor was a 2008 328i.

335dlci. I looked closely at the ends and saw the concave surface and realized they should face down to grip the black end rings' connection point. I agree with you. The labels on the bars should point down. I got the salvage panel complete with good boots for $15. The yard guy and I had to hunt through 3 different cars before we found a good one. First one was melted and second one broken in half. Both had good removable boots though.

I gotta look in the Denver area for some old junk yards like you have in texas for some m3 bits

[BB_cuda]

What i didn't mention in last weekend's work was i stripped a thread in that newly added stud spot (driver's side end, most outboard spot) on the boomerang. I was retorquing all of the fasteners to 25 lb-ft and the one just kept turning. I knew i was in trouble. I tried a couple of things. First, i used dremel to cut a slot in the top of the stud. The idea was to use screw driver to hold stud from spinning and then use box end 13 mm wrench to tighten. NOPE! The stud just kept rizing up as i turned the wrench as i was shearing off the aluminum threading. I took stud back out and ran an M8x1.25 tap in there. There wasn't much left to depend on the "threads". So, we found another M8 nut and rigged it for the time being. I put a nut above and below the boomerang and simo torqued both. I then held bottom with same 13 mm box wrench while i torqued top to 25 lb-ft.

Long term, i wanted to do the repair. I was either going to
1) helicoil back to M8x1.25
2) tap the thread for M10x1.5 and buy matching stud and nut
3) doing something not traditional

I went to auto parts store and looked at heli coil kit. It cost $29 and did not come with req'd 21/64" drill bit. The helicoil insert looked a hair short too. I went to next door Ace h/w. They had 21/64" bit for $6. So, method 1 would be $35.

I went back to look at the studs at Ace. They didn't have a continuous M10x1.5 stud like i had imagined. This ruled out method 2 that I had envisioned. My thought was if i was doing the helocoil that it is really tapped to a larger size so why not just go with larger stud and not mess with it. The tap that came with the helicoil kit didn't say what it's external threading was. It only said it was for installing the M8x1.25 helicoil.

Anyway, I found a different type of stud that I had never heard of. A portion was M10x1.5 with a neck in the middle and then the rest of the length was M8x1.25! The idea i then got was tap the boomerang for M10x1.5 and hide the fatter end of this stud in the larger hole but the external portion of stud would be no different that n before. I did this precisely and the repair was way cheap in comparison. I already had the M10x1.5 tap. I only needed the pilot drill for the M10 (which was coincidentally 21/64" bit) and this wierd "hybrid" stud. I bought these both for $9.32.

The tapping went off with out any issues. The only thing was I needed to position the stud's neck where it would barely be sticking out of the top of boomerang. This was so that I could screw the M8 nut down far enough to clamp properly. I mocked this height of stud up and had about 1/4" too much M10 sticking out of the bottom. No problem. I used my stud shortening trick yet again as i had a spare M10 nut from a previous project. I took stud out and spun the M10 nut way past where i needed to trim. Dremeled it off pretty quickly and used the M10 nut to deburr the cut. All worked perfectly.

I reinstalled the stud into the M10 tapped hole and positioned the neck to right height and slapped the bar back on there. Problem solved. I am attaching a picture of this hybrid stud. I'm sure there is a proper term for this. Picture is from bellmetric but their part is $4 versus cheaper one i got. Yes, it isn't stainless steel. It's black oxide finished.

Here is a link to the bellmetric stud I put in the picture. Sorry, no pic of the as trimmed stud. I had no blue loctite to hold it in. That is on the list to do though.
https://www.belmetric.com/metric-ste...jisp21tr4e12k3

[BB_cuda]

I completed the M3 suspension conversion this past week. Here are some pictures of all of the removed 335D parts. I don't plan to write a DIY as there are several over on the suspension/brakes/chassis sub forum. I set the ride height about 1/4" higher than OEM sport on the front AND NO MORE SCRAPE on the bumper's chin when i go in or out of the driveway. I went about 3/16" up in the back to maintain a similar rake rear to front.
Rear Suspension:
Overall, the rear suspension was the bulk of the work. I dropped the rear subframe to do both the bushings and the M3 sway bar swap. I reused the 335D rear sway bar end links. Same length as rear M3 ones. I may op to go to adjustable length ones here. I did not use the M3 toe links as they don't fit onto 335 frame and knuckles. I bought aftermarket Bimmerworld adjustable toe links with spherical bearings http://www.bimmerworld.com/Suspensio...Arm-Set_2.html. The rear subframe bushings (Powerflex Black) were impossible to get into the frame. I called Powerflex USA and got permission to cut them in half. They are in process of redesigning to go to 2 piece config. There is a steel insert that goes up within both halves. Front subframe bushings are already 2 piece by design. The HP Autosport bushing puller was a nice thing that I rented ($69 for 2 weeks). I did bend the threaded rod in my futile effort to get the rear bushings in before cutting them. HP Auto only docked me $15 to replace the threaded rod out of the $300 up front deposit. It comes with a bearing to keep the nut from binding up. It is sort of tense to get the hubs up to proper ride height before doing final torquing on the rear links. The car lifted up off jack stands as the rear springs are 550 lb/in stiffness (I'm using a Ground Control coilover/M3 conversion kit). http://www.ground-control-store.com/.../II=903/CA=268. Note: The link shows kit p/n 2091.78 which includes the rear camber arms. I used p/n 2091.01 which deleted those arms as i had scored used ones at the salvage yard. Saved $400 ($500 more in this kit versus $50 each at Lonestar Imports in H town). Ground Control did have to upcharge me $50 for steel spring supports.
Differential bushings:
After getting the sub frame reattached back to chassis and all other M3 links, sway bars, etc installed and final torqued, I had to use the trans jack to lower the diff back down to change its bushings. This really bit. Hindsight would have been to change the diff bushings when i did the Wavetrac LSD swap in February of this year. I was able to leave the driveshaft and 1/2 shafts still connected though so it wasn't a total redo.

I had to devise my own puller for the differential bushings as the HP Auto threaded rod was much too big to go through central hole. I used a 2-3/8" hole saw as the receiver cup with a 7/16" threaded rod for front diff bushings and a 3-1/2" hole saw to do the rear larger diff bushing. Make sure the cup is deep enough to let the old bushing come all the way out otherwise you will break the threaded rod. Ask me how i know. Luckily, I had a 3 foot long piece of threaded rod to make new one when previous was broken.

One comment for those that go to the finned diff cover. The rear powerflex bushig came with a 0.093" thick large diameter washer. I couldn't get washer and aluminum spacer to fit. I had to grind off 0.093" from the aluminum spacer to get things to fit. That's the way mods go though. I reinstalled the dog bone onto back of the Powerflex bushing as before.
Front Suspension:
Much more straight forward here. Only thing to watch out for is the use of the pass through style ratchet and socket. You need a 21 mm for the 2 ball joints on the wishbones. You can't buy it as a set from Sears in the 1/2" drive. 21 mm not available in 3/8". FYI, gearwrench (p/n 891226) sells a nice set that has sizes 15 mm and larger but its a standard plus metric set. You can buy the gear wrench sockets piece meal though. I've read the gearwrench set is compatible with my craftsman links given below.
Ratchet: https://www.craftsman.com/products/c...-axess-ratchet
21 mm socket: https://www.craftsman.com/products/c...1-2-inch-drive
extension (needed for the tension strut ball joint): http://www.sears.com/craftsman-3inch...FZEFDAodjaMJjg

Of course I had to break something. There is a small link that connects the left lower wishbone to the head light leveling sensor. I removed this for the wishbone switchover. I reattached the link to the leveling sensor. After all 4 links were switched, it was time to do the front strut/spring assemblies. I followed advice from youtube link and "leaned the strut outboard without needeing to compress the spring. But i broke the little connecting rod in the process. Luckily i had a spare one from the bone yard trip when i got all of the M3 links. The 335D original one was in the best shape and of course I tore that one up. The E92 M3 one sufficed and i learned leave this damn thing disconnected until you are really sure you are done. Luckily, It didn't damage the sensor or any of the linkage that is part od the sensor assembly.

Use a torx tip going through the pass through to keep ball joint from spinning (i think it was a T40). I had to turn the steering rack all the way to one extreme or other to not let it move while loosening or tightening the ball joints. You don't have to use a puller as they come apart easily after the nuts are removed. I was able to remove the strut/spring assembly without compressing the spring but i have sport suspension so the spring might be a little shorter than standard 335 suspension, IDK. As taught by the several threads, i put the blue painters tape on the fender lip edge. I reused the front sway bar links here too. the front M3 ones are about 2" longer and were a definite no go. No need for adjustable end links here.

VWetish differential lock down kit: I ran into a minor snag here. The provided 140 mm bolt was a bit too short so I had to buy a 150 mm one. The bracket is installed on the diff cover but rest of kit not installed yet. I had to go to alignment place and wanted it not to be in the way. I will finish this and add in a picture. I am including a picture of how i trimmed the diff cover bracket though. The bracket will fit an OEM cover without cutting but needed to be cut to work with my finned diff cover.

[Yozh]

Nice write up. Now, tell us how it rides.

[dmanb2b]

Great job Cuda...very interested in ride quality as well

[BB_cuda]

It's pretty tight I'll have to say. I got to drive us to the movies and took a corner pretty aggressively and it had very little body roll. There is a road on way to GF's home town called snake river road. It will be a great test for it.

[BB_cuda]

Well, 2 years later and I took my car through its paces on snake road. My GF laughed at me as i called it snake river road. Snake river is one Evil Knievel tried to jump over way back in 1974. I digress.

I took corners at decent speeds and love how flat car stays in corners. Better yet, I drove on the Mississippi River levee roads in a different part of same area. The levee roads were even more fun than the snake road. I hit low triple digits as i stomped pedal at apex and powered out of corners.

I used to think my car was too stiff and road harshly. Now i love it and how it handles on these back roads in Louisiana.